Using data from the Child Health and Development Study (CHDS) birth cohort at the Oakland Kaiser Foundation, it was found that, out of nearly 20,000 individuals born to mothers participating in the Kaiser health plan between 1959 and 1966, almost 12,000 continued to participate in the program until at least age 30. Of these, 186 individuals had been hospitalized within the Kaiser system with sufficient information in their charts to make a presumptive diagnosis of schizophrenia. In addition to the hospitalized patients, 1700 individuals from the same cohort were seen in Kaiser's Outpatient Psychiatric Clinic during 1995; presumably, some of these will also be schizophrenic. In order to confirm the diagnosis for the 186 previously hospitalized patients, face-to-face diagnostic interviews were begun this year. These diagnostic interviews are scheduled to continue until the end of 1997. Once a diagnosis of schizophrenia is confirmed, the prenatal records collected throughout the three trimesters of each subject's gestation will be examined for associations with the later development of schizophrenia. Furthermore, frozen serum has been preserved from each trimester of these pregnancies. Among other things, the serum will be examined for antibody titers to suspected viral agents felt to be prenatally involved in schizophrenia.